Diplomats and opponents of Cuban President Fidel Castro are not convinced his release of ailing dissidents in recent weeks marks a major change.

On Thursday, poet and journalist Manuel Vazquez Portal, 52, became the sixth of the 75 dissidents rounded up during a major crackdown on the opposition in April 2003 to be released.

He had been serving an 18-year jail term.

Since April 14, Mr Castro’s Government has released 10 political prisoners, a figure that rises to 14 if four dissidents on conditional release are included.

The four had been sentenced to prison terms by a trial in Ciego de Avila on April 26.

“Really, they are jittery. One feels like saying: ‘How about trying a bit harder?’” one European diplomat said.

The diplomat stresses that the European Union, which froze relations with Cuba after last year’s crackdown, is waiting for bigger gestures.

A big gesture would be the release of the most prominent dissidents, including poet and journalist Raul Rivero and economist Marta Beatriz Roque.

All of the released dissidents had health troubles prior to their imprisonment.

According to another European diplomat, the isolated Cuban Government is gradually trying to improve its image after the considerable negative fallout from its crackdown last year.

However, a US diplomat says that the releases “really are designed to divide the European Union” between those backing a resumption of dialogue with Cuba and those holding out for bigger change from the only one-party communist government in the Americas.

“Amnesty International (AI) welcomes the release of two further prisoners of conscience by the Cuban authorities but calls for more to be released,” the London-based rights group said in a statement.

“AI recognises a further 78 prisoners of conscience in Cuba and calls on the authorities to immediately and unconditionally release them all.”

On June 11, France officially welcomed the release of five dissidents, calling it a positive gesture and expressing hope that it would be a prelude to the freeing of all others.

The Government is apparently not seeking a domestic political boost from the releases, which have not been covered in official media or commented on by Government officials.

Dissidents say the releases are not a sign of something new from the Government.

“They were released because of their ill health. They don’t want them to die in prison, given the likely international impact. It is not, in my opinion, any trend,” Vladimiro Roca, president of the outlawed Cuban Social Democratic Party, said.